Why do hippos sweat red?
Show answer & explanation
Answer: Sunscreen and antibiotic secretion
Red color attracts mates — Wrong. Red secretion isn't sexual display—it's protective. Pigmented mucus provides sunscreen and antibiotic benefits for skin health.
Sunscreen and antibiotic secretion ✓ — Correct! Multipurpose skin secretion! Hippos secrete reddish oily fluid (not sweat or blood!). Contains: (1) Hipposudoric acid (red pigment). (2) Norhipposudoric acid (orange). Functions: (1) Sunscreen—absorbs UV light (hairless skin vulnerable). (2) Antibiotic—prevents infection from wounds/water bacteria. (3) Moisturizer—prevents skin cracking. Starts colorless, turns red-orange when exposed to air. Called 'blood sweat' (misnomer). important protection for semi-aquatic lifestyle!
Warning signal to predators — Wrong. Red secretion isn't warning—it's skin protection. Hipposudoric acid provides sunscreen and antibiotic properties, not predator deterrence.
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